Hello Kabeer,

I don't know if you found a solution but I came across this issue as well. The only solution I found was to give CRUD rights on both tables the many2many field, not really satisfying...

I even tried to set the relation/column1/column2 parameters and create the relation model to be able to add access rights to the relation table but it is not enough...

many2many_tags and many2many_checkboxes widgets would let you select the attachment you want but it is far from the tree view list with searchbar you get with the standard many2many.

Hello Kabeer,

Try this in xml file

<field name="attachment_ids" widget="many2many_tags" />

Hello, Kabeer 

try this one in xml file <field name="attachment_ids" widget="many2many_binary" />